After months of tensions, Israel and Iran directly locked horns in Syria overnight Wednesday. Here's what we know so far:

What happened?

Iranian forces fired 20 rockets at Israel Defense Forces positions in the Golan Heights on Wednesday night. Four of the rockets aimed toward Israel were intercepted by the Iron Dome air defense system while the remaining rockets exploded on Syrian territory, the military said.

The Israeli military accused the Revolutionary Guards' Al Quds force and its commander, Maj. Gen. Qassem Soleimani, of launching the attack at the Israeli Golan Heights. The attacks was most likely in retaliation for previous attacks on attributed to Israel on Iranian bases and positions in Syria.

What about Israel?

Before the Iranian attack, the Syrian Observatory for Human Rights reported that Israel attacked targets of the Syrian military on the outskirts of Quneitra in the Golan Heights.

After the attack, Israel hit dozens of Iranian targets in Syria: Israel said its targets included weapons storage, logistics sites and intelligence centers used by elite Iranian forces in Syria. Twenty-three militants were killed in the attack, according to the Syrian observatory.

According to Haaretz's senior military analyst, the attack dealt a severe blow to embattled Syrian leader Bashar Assad’s antiaircraft forces. The Israel Air Force said five of the batteries attacked belonged to the Syrian army and were Russian-built models: SA-22, SA-2, SA-5 and SA-17.

What are Assad's allies saying?

Lebanon's Al Mayadeen, a TV network viewed as pro-Assad, Hezbollah and their allies, reported that 28 Israeli F-15s and F-16s took part in a retaliatory strike, firing more than 60 missiles.

Meanwhile, Russia's Defense Ministry said Syria shot down more than half of Israeli missiles fired in the strike.

What did Iran target?

The Israeli army said that the rockets were fired from Syria at IDF outposts on the Golan border.

The Golan Regional Council released a statement saying that several towns in the Golan were targeted by rocket fire and that residents of those towns were told to stay in shelters until notified otherwise. Israel said there were no casualties in the attack and on Thursday, though shelters remained opened in some parts of the north, residents were allowed to return to their homes.

Why now?

As the Assad regime emerges as the victor in the Syrian civil war, Iran is trying to intensify its military presence in Syria and use its territory as a sort of forward position against Israel. Senior Israeli political and security officials are determined to be proactive about foiling this Iranian effort, even at the risk of escalation.

A month ago, on April 9, there was an attack on a Syrian air force base called T4, near the city of Homs, that’s been attributed to Israel. The attack was aimed at thwarting the Iranian effort to establish air space, backed by antiaircraft systems located on the base. The air strikes killed members of the Iranian Revolutionary Guards, and senior leaders in Tehran have repeatedly said that Israel will pay a price for its aggression.

What happens now?

Israeli intelligence believed that Iran wanted to carry out a targeted and limited response, which would make it clear to Israel that there’s a price for repeated attacks in Syria, but would not want to drag the region into war.

Now that such an attack has taken place, another possibility is that Iran will target Israeli assets abroad, such as an embassy or a group of tourists. Generally such attacks involve lengthy planning. In the past, Iranians and Hezbollah were involved in attacks against Israeli targets in Argentina (in the 1990s) and Bulgaria (in 2012). Another option is revenge through a Hezbollah attack, but it seems that the group would prefer to avoid that at this point.

How does the Iran deal play into this?

According to Haaretz's Amos Harel, it is too early to predict the repercussions of Trump’s announcement. The U.S. administration has not clarified how it will implement its withdrawal from the nuclear agreement, or how stringent the renewed sanctions will be and how quickly they will take effect. It is hard to believe Trump's decision will lead to a military escalation between Iran and the United States and Israel.

Haaretz.com, the online edition of Haaretz Newspaper in Israel, and analysis from Israel and the Middle East. Haaretz.com provides extensive and in-depth coverage of Israel, the Jewish World and the Middle East, including defense, diplomacy, the Arab-Israeli conflict, the peace process, Israeli politics, Jerusalem affairs, international relations, Iran, Iraq, Syria, Lebanon, the Palestinian Authority, the West Bank and the Gaza Strip, the Israeli business world and Jewish life in Israel and the Diaspora.